But there is evidence that we do evolve. I'll give you an example. In areas of west Africa where malaria is endemic there is an allele of hemoglobin that confers resistance when heterozygous. In other environments that allele is not beneficial and is, in fact, deleterious. It is fatal when homozygous. Now according to evolutionary theory such an allele should decline where it offers no benefit. Studies show that this allele is less frequent by about 2 percentage points in Americans of west African ancestry.
Label: Sarcastic